Type-bar action.



H. ETHERIDGE. IVTYPEV BAR ACTION. APPLICATION FILED MAR. 22,1916:

Patented Jan. 16, 1917.

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ETHERIDGE, F LONDDN, ENGLAND, ASSIGNOR TO THE BAR-LOCK TYPE- WIFIITER COMPANY LIMITE D, OF LONDON, ENGLAND.

TYPE-BAH, ACTION.

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in Type-Bar Actions, .of which the followsix . laterally v roller E ing is a specification. v

This invention relates to type-bar actions and has for its object to provide a durable tor-mi of type-bar mechanism which will .give'acceleration of the type-bar throughout the whole of the downward movement of the key it Imcessary.

One t'eature oi" the invention consists in providing the keys with a projecting tongue which carries the means 'for operatively connecting it to the sub-lever, which tongue enables the interconnecting means to be applied at different distances from the key according to the position in which the key is set in the machine.

In the accompanying drawings which illnstrat-e'one method of carrying out this invention :--l igu're 1 is a side elevation oi. thetype-har mechanisn'i in the position of rest, and Fig. 2 is a side elevation of the same shown on a smaller scale and with the parts in the striking position.

The same letters indicate the same parts in both figures.

The frame shown in section at A may be a segmental member such as is commonly employed to carry the type-bars oil a typewritc and the type-bars B are pivoted thereto at B and assume an approximately horizontal position when at rest. Each type-bar has a short operating arm B which is connected by a link C to the free end of a snb'lever D. The sub-lever is approximately vertical when in the position of rest and is pivoted at its lower end at D Each sub-lever is provided with a key-lever E for operating it. The key-lever is pivoted at E at a point behind and above the point I) about which the sub-lever is pivoted The key-lever has a lateral tongue or depending'portion E which carries a The roller is secured by a. large headed screw or rivet E the' head of which provides a shoulder to keep the sub-lever D in place against the pendent portion ot' the key-lever E. The sub-lever is slotted at D the upper end of the slot D being made suiiiciently large to allow the *1 need of the r vet which carries the roller E Specification of Letters Patent. Application filed March-22, 1916.

forward to the limit of downward, the line X-X the angle between the path Patented Jan. MS, 191 47. Serial 1 \l'o.85,806.'

to pass freely through it, but the part D of the slot is narrower, so that once the roller and its headed rivet are in position, the parts cannot be disconnected without bringing the rivet and its roller back to the enlarged portion D It will be seen that the sub-lever is approximately perpendicular to the keylever as the latter is in the horizontal position when at rest, and the 'sub-lever, as has already been stated, is approximately vertical, and across the angle formed between these two members a spring F is stretched, one end being connected to the sub-lever and the other end to the key-lever, so that the tendency of the spring is to always keep the key-lever raised and the sub-lever pulled its movement, that is to the vertical position. It should also be observed that the spring F the roller E in contact with face of the slot 1) so avoided. I

The operation of this mechanism follows :-W hen the key-lever the roller E the working that back-lash is is as is depressed, made to travel along the curved path indicated by the chain line XX. The chain-line passes through the point where the roller E" is in @contact with the rear side of the slot D of the sub-lever, and it will be seen that from this point makes an acute angle with the line or path upon which the said rear face lies, this angle widening out on the side which is toward the pivot-point I). It follows therefore that-as the roller, which may be considered the part of the key-lever E which is in engagement with the sub-lever 1) rolls down the said rear side of the slot I) and moves 'rearwardly along the path X-X, the sub-lever I) will be.

forced back, and further,

as the roller approaches the pivot-point'l) of the sub-lever, XX and the line upon which the rear face of the slot D lies will be increased. This means that as the key-lever is pressed down with an even movement, the sub-lever will be pushed back with an accelerated movement due partly to the changi1 1g anglewhicli the rear face of the slot 1) makes with the path X-X and, partly to the fact that the roller E is all the time getting closer to the pivot-point D of the sub-lever; The movement of the sub-leverof course raises'the type-barby means of the link C, and the tyne-bar'when always keeps it strikes the platen is approximately vertical as shown in Fig. 9 and the other parts assume the ditl'erent positions shown in that figure. ()wing to the accelerated movement the type-bar completes its stroke with a sharp action, which gives a clear inn ression and what is commonly known as a light action is obtained because so little eii'ort is required to move the parts at the commencement of the downward movement of the kcy-lever. The depression of the key-lever and the throwing back of the sub-lever stretches the spring F so that'as soon as the key-lever is released the said spring draws the parts back again to the position shown in Fig. 1. Obviously the degree of accele ation may be varied as required by varying the angle of the slot D relatively to the path XX. In the case shown in the drawings, the slot 1) is radial to the point of pivoting D of the sub-lever. It will be readily seen that it the slot D were so directed that the rear face which constitutes the driving-face was set on a line which would pass to the forward side of the center otthe pivotpoint D, the degree of acceleration would be increased.

The mounting of the roller E upon a depending tongue secured to the key-lever E is a feature of importance, as in addition to enabling the parts to be arranged to give the accelerated movement already mentioned, it constitutes aconvenient means of adjustment in manufacture.

It will be appreciated that the sub-levers require to be of varying length according to the position of the type-bar on the segmental are which any particular sub-lever is to operate, and this necessitates that the pin and slot connection, that is, the roller E and slot D also need to be adjusted, so that the shorter and longer levers shall all give the requisite movement to their respective type-bars, the degree of depression for each key-lever being maintained the same throughout. With .the arrangement shown, the key-levers E can all be stamped out as multiples one of the. other, the tongue it) being left long enough for the longest tongue required. This saves multiplicity of tools in the production of the parts. All

that is then necessary is to drill a: hole for the interconnecting stud Or the pin which carries the roller E at different heights in the, different keys for the purpose ofthe adjustment already referred to. The sublevers also can all be stamped out to one length and then shortened at the end which receives the link C, the shortening being done at the same time as the hole is punched forpivoting the link 0 to the lever. This feature of the invention 15 independent of whether the slot D is arranged to accelerate the. type-bar throughout the whole of the stroke or not, but has been invented as the most convenient means for giving the desired continuous acceleration.

What 1 claim as my invention and desire to secure by Letters Patent is 1. ln type-bar mechanism for a typewriter. the combination of. a type-bar, a pivoted sub-lever operativcly connected therewith, a key-lever situated approximately at right-angles to the sub-lever and having a tongue which lies approximately parallel with the subdcrer, a projection sccured to the tongu and having sliding cirgagement with a driving-tacc on the sublever, the arrangement of the parts being such that the said projection travels in a path which is toward the point of pivoting of the sub-lever but inclined also to one side of the same in the direction in which the sub-lever is to be moved whereby the sub-lever is swung about its pivot with an accelerated movement which may be made to continue throughout the whole oi the strolu and the tongue allows the projection to be situated at different points along its length, substantially as and or the purpose set forth.

2. In typebar mechanism for a typewriter, the combination of, a type-bar, a

pivoted sub-lever in the form of a plain arm so that it can be shortened as required, said sub-lever being operativelv connected with the typebar and having a slot radial to its pivot, a key-lever situated :qmroximately at right-angles to the sub-lever and having a tongue which lies approximately parallel with and at the side of the sub-lever, a projection secured to the tongue and engaging the slot in the sub-lever. the arrangement of the parts being such that the said PIOJOC- tion travels in a path which is toward the point of pivoting ot' the sub-lever but inclines also to one side of. the same in the di rection in which the sub-lever is to he moved whereby the sub-lever is swung about. its pivot with an accelerated movement which may be made to continue throughout the whole of the stroke and the tongue allows the projection to be situated at dittereut points along its length, substantially as and for the purpose set forth.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

HERBERT ETHERIUGF.

Witnesses HAROLD H. Simmons, A. M. HAYWARD.

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